Convicted Singaporean match-fixer Wilson Raj Perumal is categorically denying a story published by German weekly Der Spiegel alleging that the Cameroon team was involved in fixing a World Cup game in Brazil .

The Cameroon federation -- known as FECAFOOT -- has pledged to investigate Der Spiegel 's allegations , which focused on the national side 's second Group A game against Croatia -- purportedly based on an interview with Perumal .

`` Contrary to the ` revelations ' published by the German weekly Der Spiegel that were picked up by news outlets worldwide , I did not predict the result of the Cameroon vs. Croatia match played on June 18 , 2014 , '' said Perumal in a statement published online .

`` The Facebook chat with the Der Spiegel journalist took place a few days after the match -- June 21 -- as confirmed by my Facebook log , and was but an informal assessment of the behavior of the Cameroon team at the Brazil 2014 World Cup after they had played two of their three group stage matches , including the one with Croatia . ''

CNN has been sent screen grabs of two Facebook conversations between Perumal and the journalist , Rafael Buschmann , by the fixer 's representative .

The first is dated the June 21 and the second is dated the June 26 -- in other words after the Croatia game -- where Perumal talks of `` five to seven black sheeps , '' and `` seven rotten apples '' within the Cameroon team , adding `` in my opinion they fixed all three matches . ''

Perumal 's Facebook account does not show public updates , so CNN was unable to independently verify those exchanges .

`` At no time did I make reference to four goals being scored or to a red card being issued , '' Perumal said .

`` At no time did I suggest that I had any way of corroborating or substantiating what was meant to be an educated guess based on my extensive match-fixing experience , '' added Perumal , who was arrested in Helsinki in 2011 and sentenced to two years in prison for fixing games in Rovaniemi , northern Finland .

`` Last but not least : at no time was I informed by the Der Spiegel journalist that our chat was going to end up in the German publication . ''

The Der Spiegel journalist , Rafael Buschmann , told CNN that the publication was confident in its reporting of the story .

`` We firmly stand by our assertion that Mr. Perumal wrote in a Facebook chat with Der Spiegel some hours before the World Cup match Croatia vs. Cameroon , that the result of the match will be a 4-0 victory for Croatia and that a player of Cameroon will get a red card in the first half , '' Buschmann said .

That alleged prediction largely came true .

Midfielder Alex Song was red-carded during the game for lashing out at Croatia striker Mario Mandzukic , who scored twice in a 4-0 victory along with goals from Ivica Olic and Ivan Perisic .

CNN contacted Song 's agent but he was not immediately available for comment .

Now living in Hungary , Perumal recently published a book -- `` Kelong Kings '' -- about his involvement in illegal match fixing , which was written in conjunction with investigative journalists Alessandro Righi and Emanuele Piano .

`` I apologize to the Cameroon FA and to its fans if I inadvertently offended them ; it was not my intention , '' said Perumal . `` I strongly believe that Der Spiegel should also do the same since they placed words in my mouth that I did not utter . ''

`` Kelong Kings '' examines three decades of match-fixing efforts , including World Cup qualifiers , Olympic matches and the 2010 World Cup .

`` I am now back in Hungary where I have testified against my former associates in a local match-fixing trial , '' said Perumal .

'' ` Kelong Kings ' is an honest account of what my life has been like until today .

`` I have now turned a new leaf and wish to put my expertise at the disposal of those willing to truly fight the scourge of match-fixing .

`` When the time is ripe I will share what I know with FIFA and UEFA , but I will not accept that my statements be manipulated at the detriment of others . ''

A FIFA spokesperson told reporters Tuesday that football 's governing body could not comment on whether an investigation was underway on the alleged manipulation of the Cameroon-Croatia match .

FECAFOOT said in a statement Monday that `` in 55 years of existence , it has never been sanctioned for , involved in , or even linked to match fixing or any fraud of any kind . ''

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Match-fixer denies predicting Cameroon would lose 4-0 to Croatia at World Cup

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German magazine reported Wilson Raj Perumal told journalist result before game was played

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Perumal admits having conversation but said it took place after match

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Der Spiegel and journalist Rafael Buschmann stand by the original story